Bed and cylinder printing press



July 10, 1934. c. B. COTTRELL, 3D

BED AND CYLINDER PRINTING PRESS Filed Dec. 14, 1931 4 Sheets-Sheet 1ATTORNEYS July 10, 1934.

C. B. COTTRELL, 3D BED AND CYLINDER PRINTING PRESS Filed Dec. 14, 1931 4Sheets-Sheet 2 I 1, rydefl n ll l I N NI fin N M. mm mm W m .Nm 7 l M Jg l M e AW N M HN 3%.

ATTORNEYS July 10, 1934.

c. B. COTTRELL, an

BED AND CYLINDER PRINTING PRESS Filed Dec. 14, 1931 4 Sheets-Sheet 5INVENTOR WW? III] II II II IIIIIIIII'IIIIIIIL Fill} a J W ATTORNEYS C.B. CCTTRELL, 3D

BED PND CYLINDER PRINTING PRESS July 10,. 1934.

Filed Dec. 14, 1931 4 Sheets-Sheet 4 mvENTOR ATTORNEYS V pressioncylinder grippers,

Patented July 10, 1934 UNITED STATES 1,966,061 BED AND CYLINDER,-PRINTING PRESS Calvert B. Cottrell, 3d, Westerly, 11.1., assignor to C.B. Cottrell & Sons Company, Westerly, R. I.,

a corporation of Delaware Application December 14, 1931, Serial No.580,863

8 Claims.

My invention comprises certain improvements in a bed and cylinder presswhereby the oscillating impression cylinder is arranged to'take anunprinted sheet on its forward or printing stroke and to transfer theprinted sheet tail end first on its reverse or non-printing stroke.

A practical embodiment of my invention is represented in theaccompanying drawings in which:

Fig. 1 represents a side elevation of my improved bed and cylinderprinting press, the parts being shown in full lines in the positionsthey assume just after the bed and cylinder have started on theirforward or printing stroke, and in dotted lines in the positions theyassume at the end of the said forward or printing stroke;

Fig. 2 represents a similar view with the parts shown in the positionsthey assume when the bed and cylinder are partway of their reverse ornon-printing stroke; the inking mechanism in this view being shown indotted lines, moved to a point where its distributing and form rollerscan be readily washed without removal;

Fig. 3 represents a detail side View partly'in section on an enlargedscale, of a suitable means for operating the impression cylindergrippers, the sheet feed stop and the device for stripping the sheetstail end first from the impression cylinder;

Fig. 4 represents a detail top plan view partly in section, of some-ofthe parts shown in Fig. 3;

Fig. 5 represents a detail view partly in section, of the mechanism foroperating the movable pin which controls the tumbler cam of the imthepin being shown held in its operative position in the path. of the camby its cam on the form bed whichcontrols the closing of the grippers;

Fig. 6 represents asimilar view with the tumbler pin in its, inoperativeposition out of the path of the cam and passing under the yieldingoperating cam on the form bed which controls the opening of thegrippers;

Fig. 7 represents a detail side view of the re.- ciprocating form bed,the form member in this view being shown raised into positionto bringthe form into contact with the form rollers, of the inkingmechanism onthe forwarder printing stroke of the bed;

Fig. 8 represents a similar view with the form member shown loweredintoposition to bring'the form out of contact withthe form .rollers-onithereverse or nonsprinting stroke of the-bed;

Fig. 9,represents a transverse vertical section through the bed taken inthe plane of theline IX-IX of Fig. '7, lookingthe arrows.

Fig. 10 represents abottom plan View of the upper or form member of thebed;

in the direction of Fig. 11 represents a top plan view of the lower orbase member of the bed;

Fig. 12 represents an end view of the form member;

Fig. 13 represents an end view of the base member;

Fig. 14 represents a diagrammatic view of the impression cylinder andits adjacent parts in the positions they assume just after theimpression cylinder has started on the first revolution of its forwardor printing stroke;

Fig. 15 represents a similar view just after the impression cylinder hasstarted on the second revolution of its forward stroke;

Fig. 16 represents a similar view as the impression cylinder reaches theend of its forward stroke during the second revolution and is ready tostart on the first revolution of its reverse or non-printing stroke;

Fig. 1'1 represents a similar view as the impression cylinder passes thegripper opening point during its first revolution on its reverse stroke;

Fig. 18 represents a similar view as the impression cylinder reaches theend of its first revolution on the reverse stroke;

Fig. 19 represents a similar view as the impression cylinder reaches theend of its reverse stroke during its second revolution.

The main frame of the printing press is denoted by 1. The form bed whichis fitted to reciprocate in the main frame is shown as comprising anupper or form. member 2 and a lower or base member 3', the upper memberserving to carry the printing form. 4 and having a limited A diagonalsliding movement on the lower or base member 3 longitudinally of the.press, in the presentinstance by providing the upper or form member 2.with an inclined bottom surface and the-base member 3 with a coactingreversely inclined top surface.

A lost motion connection is provided between the form and base membersand the two members are slidably interlocked against lateraldisplacement. as follows:

The bottomrsurface of the form member 2 has longitudinal grooves 5-which. terminate at the rear end of the form member. ina cross recess 6.The top surface of the base member 3 is provided with longitudinal ribs'7 located in the longitudinal grooves 5., a cross rib 8 at the frontend. of the base member overlapping the front endof the-form. memberanda cross rib 9 at the rear end of. the base member located in thecross recess 6. of the form member. The front cross rib. 8 of the basemember serves to limit the forward and upward Sliding movement of theform member on the base member and the rear cross rib 9 serves to limitthe rearward and downward sliding movement of the'formmember on the'basemember.

posed fixedly mounted cylinders 13 and 14 below the form bed. The thecylinder 13 is connected to an arm 16 depending from the front end ofthe form member moving the'bed rearwardly and the piston 17 which slidesin the cylinder 14 is connected to an arm 18 depending from the rear endof the form member 2 for moving the bed forwardly. As this bedreciprocating means forms no part of the present invention it will notbe more specifically described herein, it being understood that suitablemotive fluid connections are provided to ensure the reciprocation of thebed by the pumps 11 and 12.

The inking mechanism is shown as comprising an ink fountain l9,distributing rollers 20, form rollers 21 continuously in one directionto ensure an even application of the ink to the form 4 on the forward orprinting stroke of the bed.

This inking mechanism reciprocating bed and it whole lengthwise alongthe machine in the main frame 1 to a point such as that shown in dottedlines in Fig. 2 where the distributing and form rollers of the inkingmechanism can be readily washed without removing mechanism.

The oscillating impression cylinder 23 is fixedly mounted in the mainframe 1 and it is geared at all times to the reciprocating bed throughthe usual gear and rack connection 24, 25, the rack being attached tothe form member 2 of the bed so that the form and cylinder are kept inperfect register in the operation of the press. The movement of the bedis sufficient to rotate the cylinder more than one revolution,preferably about one and one-half revolutions, in each direction.

This oscillating impression cylinder is mounted above the may be shiftedas a 26 are opened to release the head end of a printed sheet after theimpression cylinder has rotated about one-half of a revolution on itsreverse stroke and are permitted to remain open until the impressioncylinder finishes its reverse stroke of substantially one and one-halfrevolutions and the printed sheet has left the cylinder. The grippersare closed on the head end of the unprinted sheet at the beginning ofthe first revolution of the forward or printing stroke of the cylinderand stay closed during substantially the one and To accomplish thisresult I provide a tumbler cam operating pin 28 which is slidablelaterally into and out of piston 15 which slides for rocking the leverto move the pin 28 into the path of the tumbler cam for closing thegrippers onto the unprinted sheet at the start of the forward orprinting strokes of the bed and the cylinder. The stud or roller on thisarm 32 of the rock lever is also arranged in position to be engagedabout the end of the first one-half revolution in the reverse stroke ofthe cylinder to release the head end of the printed sheet. This cam 34is so formed that the stud or roller on the arm 32 of the rock leverwill travel inside the cam on the forward movement of the bed and on theoutside of the cam to be operated thereby on the rearward movement ofthe bed as will be clearly seen by reference to Figs. 3, 4 and 6 of thedrawings.

The sheet feed table which may be a part of any well known or approvedsheet feeding mechanism is denoted by 35 and it is arranged to feed theunprinted sheets to the under side of the impression cylinder. Themovement of the sheet feed stop 36 is controlled by a cam 37 on thereciprocating bed, said cam being arranged to 'engage a stud or roller38 on the lower end of a rod 39 depending from the arm 40 of a rocklever pivoted at 41, the other arm 42 of which lever is engaged by aspring 43 arranged to normally hold the sheet stop 36 depressed.

The sheet delivery mechanism may also be of any well known or approvedform, that shown herein comprising the endless sheet carrier 45 and thecoacting sheet delivery rolls 46, 47.

The sheet stripper 44 is depressed into position to strip the printedsheet tail end first from the upper side of the impression cylinderimmediately after the start of the reverse stroke of the cylinder, thesaid stripper being normally held out of engagement with the cylinder bya spring 48 on the rod 49. A stripper operating cam 50 on thereciprocating bed is arranged in position to engage a stud or roller 51on the rod 49 to depress the said stripper into engagement with theimpression cylinder at the proper time to strip the tail end of theprinted sheet therefrom.

The operation of the printing press is as follows:

form bed and impression cylinder are started on their forward orprinting strokes the impression cylinder grippers will be closed on thehead end of an unprinted sheet and the form member of the bed will beraised into its printing position. As the bed is moved to the end of itsforward or printing stroke the impression cylinder will be rotated aboutone and one-half revolutions and the form on the bed will have been thesheet on the impression cylinder will have with the form rollers of theinking mechanism. Also, the stripper of the delivery mechanism islowered into contact with the impression cylinder and thereby stripsprinted side up to the coacting rollers 46, 4-7 of the deliverymechanism, which rollers then take control of the sheet. When theimpression cylinder has rotated a short distance on its reverse stroke,in the present instance about one-half a revolution, the grippers areopened to release the head end of the printed sheet. These grippers arepermitted. to remain open during the remainder of the reverse stroke ofthe impression cylinder.

From the above description it will be seen that by feeding the unprintedsheet to the under side of the impression cylinder and by delivering theprinted sheet tail end first from the upper side of the impressioncylinder a considerable amount of waste movement of both the cylinderand the bed is eliminated, the printing of the sheet being startedimmediately after the head end is taken by the grippers at the start ofthe forward strokes of the cylinder and bed and the necessary reversemovement of the cylinder being mostly utilized in transferring theprinted sheet therefrom.

It will also be seen that the lowering of the form member on the reversestroke of the bed permits the distributing and form rollers of theinking mechanism to be driven continuously in one direction only, by amotor which is independent of the bed drive; thereby ensuring an evenworking up, distribution and application of the ink.

It will also be seen that when it is desired to wash the distributingand form rollers the inking mechanism as a Whole may be moved lengthwiseof the press to a point where the rollers can be washed without removingthem from the inking mechanism.

The inking mechanism shown and described but not specifically claimedherein forms the subject matter of my copending application filed April28th, 1931, Serial No. 533,426, of which this application is a division.

It is evident that various changes may be resorted to in theconstruction, form and arrangement of the several parts withoutdeparting from the spirit and scope of my invention, and hence I do notintend to be limited to the particular embodiment herein shown anddescribed, but

What I claim is:

1. In a bed and cylinder printing press, a reciprocating form bedcomprising upper and lower members, the lower member being movable in asingle plane, an impression cylinder mounted on a fixed axis and havingan oscillating movement through more than one revolution, means forfeeding an unprinted sheet to the impression cylinder on its forwardstroke, and means for taking the printed sheet tail end first from thecylinder on its reverse stroke.

2. In a bed and cylinder printing press, a reciprocating form bedcomprising upper and lower members, the lower member being movable in asingle plane, an impression cylinder mounted on a fixed axis and havingan oscillating movement through more than one revolution, means forfeeding an unprinted sheet to the underside of said cylinder on itsforward stroke, and means for taking the printed sheet tail end firstfrom the upper side of the cylinder on its reverse stroke.

3. In a bed and cylinder printing press, a reciprocating form bedcomprising upper and lower members, the lower member being movable in asingle plane, an impression cylinder mounted on a fixed axis and havingan oscillating movement through more than one revolution, means forfeeding an unprinted sheet to the impression cylinder at the beginningof its printing stroke, and means for taking the printed sheet tail endfirst from the cylinder at the beginning of its nonprinting stroke.

4. In a bed and cylinder printing press, a reciprocating form bedcomprising upper and lower members, the lower member being movable in asingle plane, an impression cylinder mounted on a fixed axis and havingan oscillating movement through more than one revolution, means forfeeding an unprinted sheet to the under side of said cylinder at thebeginning of its printing stroke, and means for taking the printed sheettail end first from the upper side of said cylinder at the beginning ofits non-printing stroke.

5. In a bed and cylinder printing press, a reciprocating form bedcomprising upper and lower members, the lower member being movable in asingle plane, an oscillating impression cylinder mounted on a fixed axisand having sheet grippers, means for closing the grippers at apredetermined point in the forward stroke of the cylinder to grasp thehead end of an unprinted sheet and for opening the grippers at saidpredetermined point to release the printed sheet on the reverse strokeof the cylinder, and means for taking the sheet tail end first from thecylinder during said reverse stroke.

6. In a bed and cylinder printing press, an oscillating impressioncylinder mounted on a fixed axis, means for feeding unprinted sheetsthereto, means for taking the printed sheets therefrom tail end first, areciprocating form bed comprising upper and lower members, the lowermember being movable in a single plane arranged to print the sheets onthe forward strokes of the bed, and an inking mechanism located abovethe bed having its form rollers arranged to ink the form on the forwardstrokes only of the bed.

7. In a bed and cylinder printing press, an oscillating impressioncylinder mounted on a fixed axis, means for feeding unprinted sheetsthereto, means for taking the printed sheets therefrom tail end first, areciprocating form bed comprising upper and lower members, the lowermember being movable in a single plane arranged to print the sheets onthe forward strokes of the bed, an inking mechanism located above thebed having its form rollers arranged to ink the form on the forwardstrokes only of the bed, and means for automatically lowering the formout of position to contact with the form rollers of the inking mechanismon the reverse strokes of the bed.

8. In a bed and cylinder printing press, an 0scillating impressioncylinder, means for feeding unprinted sheets thereto, means for takingthe printed sheets therefrom tail end first, a reciprocating form bedarranged to print the sheets on the forward strokes of the bed, aninking mechanism located above the bed having its form rollers arrangedto ink the form on the forward strokes of the bed, means forautomatically lowering the form out of position to contact with the formrollers of the inking mechanism on the reverse strokes of the bed, andmeans for driving the form rollers continuously in one direction only.

CALVERT B. CO'ITRELL, 3RD.

